As Constantine attempts to reconnect with his estranged son Garrett, who is deep in debt to the ruthless Nogales Cartel, he enlists the help of his Chicago mob colleague, Al Trapani (Mike Starr). As payback for the favor, Constantine orders Grace to diagnose Trapani’s girlfriend, a patient with a shocking secret who is experiencing inexplicable pains.

Grace's world crumbles as her family remains in jeopardy, the FBI closes in and Constantine reveals something that rocks her to the core. Meanwhile, longtime mobster Al Trapani (Mike Starr) becomes increasingly involved in Constantine's business, and Franco's secret leaks. As the walls begin to close in on Grace and the duality of her life cuts deeper than ever before, she makes a desperate attempt to settle her role in both worlds in the series finale.